Method and apparatus for power saving in wireless communication system

ABSTRACT

The present disclosure relates to a power saving in wireless communications. According to an embodiment of the present disclosure, a method performed by a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system comprises: transmitting, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receiving, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determining a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmitting, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receiving, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is the National Stage filing under 35 U.S.C. 371 of International Application No. PCT/KR2021/014484, filed on Oct. 18, 2021, which claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2020-0138430, filed on Oct. 23, 2020, the contents of which are all incorporated by reference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates to a power saving in wireless communications.

BACKGROUND

3rd generation partnership project (3GPP) long-term evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power consumption of a terminal as an upper-level requirement.

Work has started in international telecommunication union (ITU) and 3GPP to develop requirements and specifications for new radio (NR) systems. 3GPP has to identify and develop the technology components needed for successfully standardizing the new RAT timely satisfying both the urgent market needs, and the more long-term requirements set forth by the ITU radio communication sector (ITU-R) international mobile telecommunications (IMT)-2020 process. Further, the NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications even in a more distant future.

The NR targets a single technical framework addressing all usage scenarios, requirements and deployment scenarios including enhanced mobile broadband (eMBB), massive machine-type-communications (mMTC), ultra-reliable and low latency communications (URLLC), etc. The NR shall be inherently forward compatible.

Dual connectivity (DC) and carrier aggregation (CA) are adopted to increase a data rate in wireless communications. In the DC and/or CA, services can be provided to a UE via a plurality of cells, including at least one special cell (SpCell) and at least one secondary cell (S Cell). However, since the UE should monitor the plurality of cells in the DC and/or CA even though there are not much data to be transmitted to and from the UE, power consumption in the UE may be an issue.

SUMMARY

An aspect of the present disclosure is to provide method and apparatus for power saving in a wireless communication system.

Another aspect of the present disclosure is to provide method and apparatus for activating or deactivating one or more cells in a wireless communication system.

According to an embodiment of the present disclosure, a method performed by a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system comprises: transmitting, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receiving, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determining a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmitting, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receiving, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to an embodiment of the present disclosure, a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system comprises: a transceiver; a memory; and at least one processor operatively coupled to the transceiver and the memory, and configured to: control the transceiver to transmit, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); control the transceiver to receive, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determine a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; control the transceiver to transmit, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and control the transceiver to receive, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to an embodiment of the present disclosure, a non-transitory computer-readable medium has stored thereon a plurality of instructions. The plurality of instructions, when executed by a processor of a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC), cause the CU to: transmit, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receive, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determine a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmit, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receive, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to an embodiment of the present disclosure, a processor for a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system executes instructions which are implemented by a software code stored in a memory of the CU. The instructions perform, when executed by the processor, operations comprising: transmitting, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receiving, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determining a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmitting, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receiving, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to an embodiment of the present disclosure, a method performed by a wireless device served by a master node (MN) and a secondary node (SN) in a dual connectivity (DC) in a wireless communication system comprises: entering a secondary cell group (SCG) deactivation state for an SCG related to the SN; in the SCG deactivation state, communicating with the MN while skipping a physical downlink control channel (PDCCH) monitoring for one or more cells in the SCG that are deactivated, wherein the one or more cells comprise a primary secondary cell (PSCell); switching from the SCG deactivation state to an SCG activation state for the SCG; and in the SCG activation state, communicating with the MN and the SN while performing a PDCCH monitoring for a list of cells in the SCG that is activated, wherein the list of cells comprises the PSCell, and wherein the list of cells is determined based on at least one of: an amount of packets to be transmitted to the wireless device or by the wireless device; or a measurement report transmitted by the wireless device.

According to an embodiment of the present disclosure, a wireless device served by a master node (MN) and a secondary node (SN) in a dual connectivity (DC) in a wireless communication system comprises: a transceiver; a memory; and at least one processor operatively coupled to the transceiver and the memory, and configured to: enter a secondary cell group (SCG) deactivation state for an SCG related to the SN; in the SCG deactivation state, control the transceiver to communicate with the MN while skipping a physical downlink control channel (PDCCH) monitoring for one or more cells in the SCG that are deactivated, wherein the one or more cells comprise a primary secondary cell (PSCell); switch from the SCG deactivation state to an SCG activation state for the SCG; and in the SCG activation state, control the transceiver to communicate with the MN and the SN while performing a PDCCH monitoring for a list of cells in the SCG that is activated, wherein the list of cells comprises the PSCell, and wherein the list of cells is determined based on at least one of: an amount of packets to be transmitted to the wireless device or by the wireless device; or a measurement report transmitted by the wireless device.

The present disclosure may have various advantageous effects.

For example, UE's service experience can be enhanced in DC since UE's power consumption can be reduced if there are no data packets to be transmitted during a deactivation state and when packets arrive again, UE and network can go to connected mode quickly to receive the services.

Advantageous effects which can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand and/or derive from the present disclosure. Accordingly, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that may be understood or derived from the technical features of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

FIG. 3 shows an example of a wireless device to which implementations of the present disclosure is applied.

FIG. 4 shows an example of UE to which implementations of the present disclosure is applied.

FIG. 5 shows an example of a system architecture for a communication system to which technical features of the present disclosure can be applied.

FIG. 6 shows an example of the overall architecture of an NG-RAN to which technical features of the present disclosure can be applied.

FIG. 7 shows an example of a dual connectivity (DC) architecture to which technical features of the present disclosure can be applied.

FIG. 8 shows an example of possible RRC states in a wireless communication system to which technical features of the present disclosure can be applied.

FIGS. 9A and 9B show a first example of MR-DC with 5GC with RRC_INACTIVE to which technical features of the present disclosure can be applied.

FIGS. 10A and 10B show a second example of MR-DC with 5GC with RRC_INACTIVE to which technical features of the present disclosure can be applied.

FIG. 11 shows an example of a method for SCG deactivation according to an embodiment of the present disclosure.

FIG. 12 shows an example of a method for performing a communication in a SCG deactivation state according to an embodiment of the present disclosure.

FIG. 13 shows an example of a procedure for SCG activation/deactivation for a dual connected UE according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

The following techniques, apparatuses, and systems may be applied to a variety of wireless multiple access systems. Examples of the multiple access systems include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, a single carrier frequency division multiple access (SC-FDMA) system, and a multicarrier frequency division multiple access (MC-FDMA) system. CDMA may be embodied through radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA may be embodied through radio technology such as global system for mobile communications (GSM), general packet radio service (GPRS), or enhanced data rates for GSM evolution (EDGE). OFDMA may be embodied through radio technology such as institute of electrical and electronics engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or evolved UTRA (E-UTRA). UTRA is a part of a universal mobile telecommunications system (UMTS). 3rd generation partnership project (3GPP) long term evolution (LTE) is a part of evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in DL and SC-FDMA in UL. Evolution of 3GPP LTE includes LTE-A (advanced), LTE-A Pro, and/or 5G NR (new radio).

For convenience of description, implementations of the present disclosure are mainly described in regards to a 3GPP based wireless communication system. However, the technical features of the present disclosure are not limited thereto. For example, although the following detailed description is given based on a mobile communication system corresponding to a 3GPP based wireless communication system, aspects of the present disclosure that are not limited to 3GPP based wireless communication system are applicable to other mobile communication systems.

For terms and technologies which are not specifically described among the terms of and technologies employed in the present disclosure, the wireless communication standard documents published before the present disclosure may be referenced.

In the present disclosure, “A or B” may mean “only A”, “only B”, or “both A and B”. In other words, “A or B” in the present disclosure may be interpreted as “A and/or B”. For example, “A, B or C” in the present disclosure may mean “only A”, “only B”, “only C”, or “any combination of A, B and C”.

In the present disclosure, slash (/) or comma (,) may mean “and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B” may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C” may mean “A, B or C”.

In the present disclosure, “at least one of A and B” may mean “only A”, “only B” or “both A and B”. In addition, the expression “at least one of A or B” or “at least one of A and/or B” in the present disclosure may be interpreted as same as “at least one of A and B”.

In addition, in the present disclosure, “at least one of A, B and C” may mean “only A”, “only B”, “only C”, or “any combination of A, B and C”. In addition, “at least one of A, B or C” or “at least one of A, B and/or C” may mean “at least one of A, B and C”.

Also, parentheses used in the present disclosure may mean “for example”. In detail, when it is shown as “control information (PDCCH)”, “PDCCH” may be proposed as an example of “control information”. In other words, “control information” in the present disclosure is not limited to “PDCCH”, and “PDDCH” may be proposed as an example of “control information”. In addition, even when shown as “control information (i.e., PDCCH)”, “PDCCH” may be proposed as an example of “control information”.

Technical features that are separately described in one drawing in the present disclosure may be implemented separately or simultaneously.

Although not limited thereto, various descriptions, functions, procedures, suggestions, methods and/or operational flowcharts of the present disclosure disclosed herein can be applied to various fields requiring wireless communication and/or connection (e.g., 5G) between devices.

Hereinafter, the present disclosure will be described in more detail with reference to drawings. The same reference numerals in the following drawings and/or descriptions may refer to the same and/or corresponding hardware blocks, software blocks, and/or functional blocks unless otherwise indicated.

FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

The 5G usage scenarios shown in FIG. 1 are only exemplary, and the technical features of the present disclosure can be applied to other 5G usage scenarios which are not shown in FIG. 1 .

Three main requirement categories for 5G include (1) a category of enhanced mobile broadband (eMBB), (2) a category of massive machine type communication (mMTC), and (3) a category of ultra-reliable and low latency communications (URLLC).

Partial use cases may require a plurality of categories for optimization and other use cases may focus only upon one key performance indicator (KPI). 5G supports such various use cases using a flexible and reliable method.

eMBB far surpasses basic mobile Internet access and covers abundant bidirectional work and media and entertainment applications in cloud and augmented reality. Data is one of 5G core motive forces and, in a 5G era, a dedicated voice service may not be provided for the first time. In 5G, it is expected that voice will be simply processed as an application program using data connection provided by a communication system. Main causes for increased traffic volume are due to an increase in the size of content and an increase in the number of applications requiring high data transmission rate. A streaming service (of audio and video), conversational video, and mobile Internet access will be more widely used as more devices are connected to the Internet. These many application programs require connectivity of an always turned-on state in order to push real-time information and alarm for users. Cloud storage and applications are rapidly increasing in a mobile communication platform and may be applied to both work and entertainment. The cloud storage is a special use case which accelerates growth of uplink data transmission rate. 5G is also used for remote work of cloud. When a tactile interface is used, 5G demands much lower end-to-end latency to maintain user good experience. Entertainment, for example, cloud gaming and video streaming, is another core element which increases demand for mobile broadband capability. Entertainment is essential for a smartphone and a tablet in any place including high mobility environments such as a train, a vehicle, and an airplane. Other use cases are augmented reality for entertainment and information search. In this case, the augmented reality requires very low latency and instantaneous data volume.

In addition, one of the most expected 5G use cases relates a function capable of smoothly connecting embedded sensors in all fields, i.e., mMTC. It is expected that the number of potential Internet-of-things (IoT) devices will reach 204 hundred million up to the year of 2020. An industrial IoT is one of categories of performing a main role enabling a smart city, asset tracking, smart utility, agriculture, and security infrastructure through 5G.

URLLC includes a new service that will change industry through remote control of main infrastructure and an ultra-reliable/available low-latency link such as a self-driving vehicle. A level of reliability and latency is essential to control a smart grid, automatize industry, achieve robotics, and control and adjust a drone.

5G is a means of providing streaming evaluated as a few hundred megabits per second to gigabits per second and may complement fiber-to-the-home (FTTH) and cable-based broadband (or DOCSIS). Such fast speed is needed to deliver TV in resolution of 4K or more (6K, 8K, and more), as well as virtual reality and augmented reality. Virtual reality (VR) and augmented reality (AR) applications include almost immersive sports games. A specific application program may require a special network configuration. For example, for VR games, gaming companies need to incorporate a core server into an edge network server of a network operator in order to minimize latency.

Automotive is expected to be a new important motivated force in 5G together with many use cases for mobile communication for vehicles. For example, entertainment for passengers requires high simultaneous capacity and mobile broadband with high mobility. This is because future users continue to expect connection of high quality regardless of their locations and speeds. Another use case of an automotive field is an AR dashboard. The AR dashboard causes a driver to identify an object in the dark in addition to an object seen from a front window and displays a distance from the object and a movement of the object by overlapping information talking to the driver. In the future, a wireless module enables communication between vehicles, information exchange between a vehicle and supporting infrastructure, and information exchange between a vehicle and other connected devices (e.g., devices accompanied by a pedestrian). A safety system guides alternative courses of a behavior so that a driver may drive more safely drive, thereby lowering the danger of an accident. The next stage will be a remotely controlled or self-driven vehicle. This requires very high reliability and very fast communication between different self-driven vehicles and between a vehicle and infrastructure. In the future, a self-driven vehicle will perform all driving activities and a driver will focus only upon abnormal traffic that the vehicle cannot identify. Technical requirements of a self-driven vehicle demand ultra-low latency and ultra-high reliability so that traffic safety is increased to a level that cannot be achieved by human being.

A smart city and a smart home/building mentioned as a smart society will be embedded in a high-density wireless sensor network. A distributed network of an intelligent sensor will identify conditions for costs and energy-efficient maintenance of a city or a home. Similar configurations may be performed for respective households. All of temperature sensors, window and heating controllers, burglar alarms, and home appliances are wirelessly connected. Many of these sensors are typically low in data transmission rate, power, and cost. However, real-time HD video may be demanded by a specific type of device to perform monitoring.

Consumption and distribution of energy including heat or gas is distributed at a higher level so that automated control of the distribution sensor network is demanded. The smart grid collects information and connects the sensors to each other using digital information and communication technology so as to act according to the collected information. Since this information may include behaviors of a supply company and a consumer, the smart grid may improve distribution of fuels such as electricity by a method having efficiency, reliability, economic feasibility, production sustainability, and automation. The smart grid may also be regarded as another sensor network having low latency.

Mission critical application (e.g., e-health) is one of 5G use scenarios. A health part contains many application programs capable of enjoying benefit of mobile communication. A communication system may support remote treatment that provides clinical treatment in a faraway place. Remote treatment may aid in reducing a barrier against distance and improve access to medical services that cannot be continuously available in a faraway rural area. Remote treatment is also used to perform important treatment and save lives in an emergency situation. The wireless sensor network based on mobile communication may provide remote monitoring and sensors for parameters such as heart rate and blood pressure.

Wireless and mobile communication gradually becomes important in the field of an industrial application. Wiring is high in installation and maintenance cost. Therefore, a possibility of replacing a cable with reconstructible wireless links is an attractive opportunity in many industrial fields. However, in order to achieve this replacement, it is necessary for wireless connection to be established with latency, reliability, and capacity similar to those of the cable and management of wireless connection needs to be simplified. Low latency and a very low error probability are new requirements when connection to 5G is needed.

Logistics and freight tracking are important use cases for mobile communication that enables inventory and package tracking anywhere using a location-based information system. The use cases of logistics and freight typically demand low data rate but require location information with a wide range and reliability.

Referring to FIG. 1 , the communication system 1 includes wireless devices 100 a to 100 f, base stations (BSs) 200, and a network 300. Although FIG. 1 illustrates a 5G network as an example of the network of the communication system 1, the implementations of the present disclosure are not limited to the 5G system, and can be applied to the future communication system beyond the 5G system.

The BSs 200 and the network 300 may be implemented as wireless devices and a specific wireless device may operate as a BS/network node with respect to other wireless devices.

The wireless devices 100 a to 100 f represent devices performing communication using radio access technology (RAT) (e.g., 5G new RAT (NR)) or LTE) and may be referred to as communication/radio/5G devices. The wireless devices 100 a to 100 f may include, without being limited to, a robot 100 a, vehicles 100 b-1 and 100 b-2, an extended reality (XR) device 100 c, a hand-held device 100 d, a home appliance 100 e, an IoT device 100 f, and an artificial intelligence (AI) device/server 400. For example, the vehicles may include a vehicle having a wireless communication function, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. The vehicles may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device may include an AR/VR/Mixed Reality (MR) device and may be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), and a computer (e.g., a notebook). The home appliance may include a TV, a refrigerator, and a washing machine. The IoT device may include a sensor and a smartmeter.

In the present disclosure, the wireless devices 100 a to 100 f may be called user equipments (UEs). A UE may include, for example, a cellular phone, a smartphone, a laptop computer, a digital broadcast terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, a slate personal computer (PC), a tablet PC, an ultrabook, a vehicle, a vehicle having an autonomous traveling function, a connected car, an UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a FinTech device (or a financial device), a security device, a weather/environment device, a device related to a 5G service, or a device related to a fourth industrial revolution field.

The UAV may be, for example, an aircraft aviated by a wireless control signal without a human being onboard.

The VR device may include, for example, a device for implementing an object or a background of the virtual world. The AR device may include, for example, a device implemented by connecting an object or a background of the virtual world to an object or a background of the real world. The MR device may include, for example, a device implemented by merging an object or a background of the virtual world into an object or a background of the real world. The hologram device may include, for example, a device for implementing a stereoscopic image of 360 degrees by recording and reproducing stereoscopic information, using an interference phenomenon of light generated when two laser lights called holography meet.

The public safety device may include, for example, an image relay device or an image device that is wearable on the body of a user.

The MTC device and the IoT device may be, for example, devices that do not require direct human intervention or manipulation. For example, the MTC device and the IoT device may include smartmeters, vending machines, thermometers, smartbulbs, door locks, or various sensors.

The medical device may be, for example, a device used for the purpose of diagnosing, treating, relieving, curing, or preventing disease. For example, the medical device may be a device used for the purpose of diagnosing, treating, relieving, or correcting injury or impairment. For example, the medical device may be a device used for the purpose of inspecting, replacing, or modifying a structure or a function. For example, the medical device may be a device used for the purpose of adjusting pregnancy. For example, the medical device may include a device for treatment, a device for operation, a device for (in vitro) diagnosis, a hearing aid, or a device for procedure.

The security device may be, for example, a device installed to prevent a danger that may arise and to maintain safety. For example, the security device may be a camera, a closed-circuit TV (CCTV), a recorder, or a black box.

The FinTech device may be, for example, a device capable of providing a financial service such as mobile payment. For example, the FinTech device may include a payment device or a point of sales (POS) system.

The weather/environment device may include, for example, a device for monitoring or predicting a weather/environment.

The wireless devices 100 a to 100 f may be connected to the network 300 via the BSs 200. An AI technology may be applied to the wireless devices 100 a to 100 f and the wireless devices 100 a to 100 f may be connected to the AI server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, and a beyond-5G network. Although the wireless devices 100 a to 100 f may communicate with each other through the BSs 200/network 300, the wireless devices 100 a to 100 f may perform direct communication (e.g., sidelink communication) with each other without passing through the BSs 200/network 300. For example, the vehicles 100 b-1 and 100 b-2 may perform direct communication (e.g., vehicle-to-vehicle (V2V)/vehicle-to-everything (V2X) communication). The IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b and 150 c may be established between the wireless devices 100 a to 100 f and/or between wireless device 100 a to 100 f and BS 200 and/or between BSs 200. Herein, the wireless communication/connections may be established through various RATs (e.g., 5G NR) such as uplink/downlink communication 150 a, sidelink communication (or device-to-device (D2D) communication) 150 b, inter-base station communication 150 c (e.g., relay, integrated access and backhaul (IAB)), etc. The wireless devices 100 a to 100 f and the BSs 200/the wireless devices 100 a to 100 f may transmit/receive radio signals to/from each other through the wireless communication/connections 150 a, 150 b and 150 c. For example, the wireless communication/connections 150 a, 150 b and 150 c may transmit/receive signals through various physical channels. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, and resource mapping/de-mapping), and resource allocating processes, for transmitting/receiving radio signals, may be performed based on the various proposals of the present disclosure.

AI refers to the field of studying artificial intelligence or the methodology that can create it, and machine learning refers to the field of defining various problems addressed in the field of AI and the field of methodology to solve them. Machine learning is also defined as an algorithm that increases the performance of a task through steady experience on a task.

Robot means a machine that automatically processes or operates a given task by its own ability. In particular, robots with the ability to recognize the environment and make self-determination to perform actions can be called intelligent robots. Robots can be classified as industrial, medical, home, military, etc., depending on the purpose or area of use. The robot can perform a variety of physical operations, such as moving the robot joints with actuators or motors. The movable robot also includes wheels, brakes, propellers, etc., on the drive, allowing it to drive on the ground or fly in the air.

Autonomous driving means a technology that drives on its own, and autonomous vehicles mean vehicles that drive without user's control or with minimal user's control. For example, autonomous driving may include maintaining lanes in motion, automatically adjusting speed such as adaptive cruise control, automatic driving along a set route, and automatically setting a route when a destination is set. The vehicle covers vehicles equipped with internal combustion engines, hybrid vehicles equipped with internal combustion engines and electric motors, and electric vehicles equipped with electric motors, and may include trains, motorcycles, etc., as well as cars. Autonomous vehicles can be seen as robots with autonomous driving functions.

Extended reality is collectively referred to as VR, AR, and MR. VR technology provides objects and backgrounds of real world only through computer graphic (CG) images. AR technology provides a virtual CG image on top of a real object image. MR technology is a CG technology that combines and combines virtual objects into the real world. MR technology is similar to AR technology in that they show real and virtual objects together. However, there is a difference in that in AR technology, virtual objects are used as complementary forms to real objects, while in MR technology, virtual objects and real objects are used as equal personalities.

NR supports multiples numerologies (and/or multiple subcarrier spacings (SCS)) to support various 5G services. For example, if SCS is 15 kHz, wide area can be supported in traditional cellular bands, and if SCS is 30 kHz/60 kHz, dense-urban, lower latency, and wider carrier bandwidth can be supported. If SCS is 60 kHz or higher, bandwidths greater than 24.25 GHz can be supported to overcome phase noise.

The NR frequency band may be defined as two types of frequency range, i.e., FR1 and FR2. The numerical value of the frequency range may be changed. For example, the frequency ranges of the two types (FR1 and FR2) may be as shown in Table 1 below. For ease of explanation, in the frequency ranges used in the NR system, FR1 may mean “sub 6 GHz range”, FR2 may mean “above 6 GHz range,” and may be referred to as millimeter wave (mmW).

TABLE 1 Frequency Range Corresponding Subcarrier designation frequency range Spacing FR1  450 MHz-6000 MHz 15, 30, 60 kHz FR2 24250 MHz-52600 MHZ 60, 120, 240 kHz

As mentioned above, the numerical value of the frequency range of the NR system may be changed. For example, FR1 may include a frequency band of 410 MHz to 7125 MHz as shown in Table 2 below. That is, FR1 may include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or more. For example, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or more included in FR1 may include an unlicensed band. Unlicensed bands may be used for a variety of purposes, for example for communication for vehicles (e.g., autonomous driving).

TABLE 2 Frequency Range Corresponding Subcarrier designation frequency range Spacing FR1  410 MHz-7125 MHz 15, 30, 60 kHz FR2 24250 MHz-52600 MHz 60, 120, 240 kHz

Here, the radio communication technologies implemented in the wireless devices in the present disclosure may include narrowband internet-of-things (NB-IoT) technology for low-power communication as well as LTE, NR and 6G. For example, NB-IoT technology may be an example of low power wide area network (LPWAN) technology, may be implemented in specifications such as LTE Cat NB1 and/or LTE Cat NB2, and may not be limited to the above-mentioned names. Additionally and/or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may communicate based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and be called by various names such as enhanced machine type communication (eMTC). For example, LTE-M technology may be implemented in at least one of the various specifications, such as 1) LTE Cat 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) LTE M, and may not be limited to the above-mentioned names. Additionally and/or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may include at least one of ZigBee, Bluetooth, and/or LPWAN which take into account low-power communication, and may not be limited to the above-mentioned names. For example, ZigBee technology may generate personal area networks (PANs) associated with small/low-power digital communication based on various specifications such as IEEE 802.15.4 and may be called various names. FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

Referring to FIG. 2 , a first wireless device 100 and a second wireless device 200 may transmit/receive radio signals to/from an external device through a variety of RATs (e.g., LTE and NR).

In FIG. 2 , {the first wireless device 100 and the second wireless device 200} may correspond to at least one of {the wireless device 100 a to 100 f and the BS 200}, {the wireless device 100 a to 100 f and the wireless device 100 a to 100 f} and/or {the BS 200 and the BS 200} of FIG. 1 .

The first wireless device 100 may include at least one transceiver, such as a transceiver 106, at least one processing chip, such as a processing chip 101, and/or one or more antennas 108.

The processing chip 101 may include at least one processor, such a processor 102, and at least one memory, such as a memory 104. It is exemplarily shown in FIG. 2 that the memory 104 is included in the processing chip 101. Additional and/or alternatively, the memory 104 may be placed outside of the processing chip 101.

The processor 102 may control the memory 104 and/or the transceiver 106 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts described in the present disclosure. For example, the processor 102 may process information within the memory 104 to generate first information/signals and then transmit radio signals including the first information/signals through the transceiver 106. The processor 102 may receive radio signals including second information/signals through the transceiver 106 and then store information obtained by processing the second information/signals in the memory 104.

The memory 104 may be operably connectable to the processor 102. The memory 104 may store various types of information and/or instructions. The memory 104 may store a software code 105 which implements instructions that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code 105 may implement instructions that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code 105 may control the processor 102 to perform one or more protocols. For example, the software code 105 may control the processor 102 to perform one or more layers of the radio interface protocol.

Herein, the processor 102 and the memory 104 may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver 106 may be connected to the processor 102 and transmit and/or receive radio signals through one or more antennas 108. Each of the transceiver 106 may include a transmitter and/or a receiver. The transceiver 106 may be interchangeably used with radio frequency (RF) unit(s). In the present disclosure, the first wireless device 100 may represent a communication modem/circuit/chip.

The second wireless device 200 may include at least one transceiver, such as a transceiver 206, at least one processing chip, such as a processing chip 201, and/or one or more antennas 208.

The processing chip 201 may include at least one processor, such a processor 202, and at least one memory, such as a memory 204. It is exemplarily shown in FIG. 2 that the memory 204 is included in the processing chip 201. Additional and/or alternatively, the memory 204 may be placed outside of the processing chip 201.

The processor 202 may control the memory 204 and/or the transceiver 206 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts described in the present disclosure. For example, the processor 202 may process information within the memory 204 to generate third information/signals and then transmit radio signals including the third information/signals through the transceiver 206. The processor 202 may receive radio signals including fourth information/signals through the transceiver 106 and then store information obtained by processing the fourth information/signals in the memory 204.

The memory 204 may be operably connectable to the processor 202. The memory 204 may store various types of information and/or instructions. The memory 204 may store a software code 205 which implements instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code 205 may implement instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code 205 may control the processor 202 to perform one or more protocols. For example, the software code 205 may control the processor 202 to perform one or more layers of the radio interface protocol.

Herein, the processor 202 and the memory 204 may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver 206 may be connected to the processor 202 and transmit and/or receive radio signals through one or more antennas 208. Each of the transceiver 206 may include a transmitter and/or a receiver. The transceiver 206 may be interchangeably used with RF unit. In the present disclosure, the second wireless device 200 may represent a communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 will be described more specifically. One or more protocol layers may be implemented by, without being limited to, one or more processors 102 and 202. For example, the one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as physical (PHY) layer, media access control (MAC) layer, radio link control (RLC) layer, packet data convergence protocol (PDCP) layer, radio resource control (RRC) layer, and service data adaptation protocol (SDAP) layer). The one or more processors 102 and 202 may generate one or more protocol data units (PDUs) and/or one or more service data unit (SDUs) according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The one or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The one or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure and provide the generated signals to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive the signals (e.g., baseband signals) from the one or more transceivers 106 and 206 and acquire the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure.

The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in the one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software and the firmware or software may be configured to include the modules, procedures, or functions. Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be included in the one or more processors 102 and 202 or stored in the one or more memories 104 and 204 so as to be driven by the one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software in the form of code, commands, and/or a set of commands.

The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and/or commands. The one or more memories 104 and 204 may be configured by read-only memories (ROMs), random access memories (RAMs), electrically erasable programmable read-only memories (EPROMs), flash memories, hard drives, registers, cash memories, computer-readable storage media, and/or combinations thereof. The one or more memories 104 and 204 may be located at the interior and/or exterior of the one or more processors 102 and 202. The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 through various technologies such as wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, control information, and/or radio signals/channels, mentioned in the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure, to one or more other devices. The one or more transceivers 106 and 206 may receive user data, control information, and/or radio signals/channels, mentioned in the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure, from one or more other devices. For example, the one or more transceivers 106 and 206 may be connected to the one or more processors 102 and 202 and transmit and receive radio signals. For example, the one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may transmit user data, control information, or radio signals to one or more other devices. The one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may receive user data, control information, or radio signals from one or more other devices.

The one or more transceivers 106 and 206 may be connected to the one or more antennas 108 and 208 and the one or more transceivers 106 and 206 may be configured to transmit and receive user data, control information, and/or radio signals/channels, mentioned in the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure, through the one or more antennas 108 and 208. In the present disclosure, the one or more antennas 108 and 208 may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

The one or more transceivers 106 and 206 may convert received user data, control information, radio signals/channels, etc., from RF band signals into baseband signals in order to process received user data, control information, radio signals/channels, etc., using the one or more processors 102 and 202. The one or more transceivers 106 and 206 may convert the user data, control information, radio signals/channels, etc., processed using the one or more processors 102 and 202 from the base band signals into the RF band signals. To this end, the one or more transceivers 106 and 206 may include (analog) oscillators and/or filters. For example, the one or more transceivers 106 and 206 can up-convert OFDM baseband signals to OFDM signals by their (analog) oscillators and/or filters under the control of the one or more processors 102 and 202 and transmit the up-converted OFDM signals at the carrier frequency. The one or more transceivers 106 and 206 may receive OFDM signals at a carrier frequency and down-convert the OFDM signals into OFDM baseband signals by their (analog) oscillators and/or filters under the control of the one or more processors 102 and 202.

In the implementations of the present disclosure, a UE may operate as a transmitting device in uplink (UL) and as a receiving device in downlink (DL). In the implementations of the present disclosure, a BS may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 acts as the UE, and the second wireless device 200 acts as the BS. For example, the processor(s) 102 connected to, mounted on or launched in the first wireless device 100 may be configured to perform the UE behavior according to an implementation of the present disclosure or control the transceiver(s) 106 to perform the UE behavior according to an implementation of the present disclosure. The processor(s) 202 connected to, mounted on or launched in the second wireless device 200 may be configured to perform the BS behavior according to an implementation of the present disclosure or control the transceiver(s) 206 to perform the BS behavior according to an implementation of the present disclosure.

In the present disclosure, a BS is also referred to as a node B (NB), an eNode B (eNB), or a gNB.

FIG. 3 shows an example of a wireless device to which implementations of the present disclosure is applied.

The wireless device may be implemented in various forms according to a use-case/service (refer to FIG. 1 ).

Referring to FIG. 3 , wireless devices 100 and 200 may correspond to the wireless devices 100 and 200 of FIG. 2 and may be configured by various elements, components, units/portions, and/or modules. For example, each of the wireless devices 100 and 200 may include a communication unit 110, a control unit 120, a memory unit 90, and additional components 100. The communication unit 110 may include a communication circuit 112 and transceiver(s) 110. For example, the communication circuit 112 may include the one or more processors 102 and 202 of FIG. 2 and/or the one or more memories 104 and 204 of FIG. 2 . For example, the transceiver(s) 110 may include the one or more transceivers 106 and 206 of FIG. 2 and/or the one or more antennas 108 and 208 of FIG. 2 . The control unit 120 is electrically connected to the communication unit 110, the memory unit 90, and the additional components 100 and controls overall operation of each of the wireless devices 100 and 200. For example, the control unit 120 may control an electric/mechanical operation of each of the wireless devices 100 and 200 based on programs/code/commands/information stored in the memory unit 90. The control unit 120 may transmit the information stored in the memory unit 90 to the exterior (e.g., other communication devices) via the communication unit 110 through a wireless/wired interface or store, in the memory unit 90, information received through the wireless/wired interface from the exterior (e.g., other communication devices) via the communication unit 110.

The additional components 100 may be variously configured according to types of the wireless devices 100 and 200. For example, the additional components 100 may include at least one of a power unit/battery, input/output (I/O) unit (e.g., audio I/O port, video I/O port), a driving unit, and a computing unit. The wireless devices 100 and 200 may be implemented in the form of, without being limited to, the robot (100 a of FIG. 1 ), the vehicles (100 b-1 and 100 b-2 of FIG. 1 ), the XR device (100 c of FIG. 1 ), the hand-held device (100 d of FIG. 1 ), the home appliance (100 e of FIG. 1 ), the IoT device (100 f of FIG. 1 ), a digital broadcast terminal, a hologram device, a public safety device, an MTC device, a medicine device, a FinTech device (or a finance device), a security device, a climate/environment device, the AI server/device (400 of FIG. 1 ), the BSs (200 of FIG. 1 ), a network node, etc. The wireless devices 100 and 200 may be used in a mobile or fixed place according to a use-example/service.

In FIG. 3 , the entirety of the various elements, components, units/portions, and/or modules in the wireless devices 100 and 200 may be connected to each other through a wired interface or at least a part thereof may be wirelessly connected through the communication unit 110. For example, in each of the wireless devices 100 and 200, the control unit 120 and the communication unit 110 may be connected by wire and the control unit 120 and first units (e.g., 90 and 100) may be wirelessly connected through the communication unit 110. Each element, component, unit/portion, and/or module within the wireless devices 100 and 200 may further include one or more elements. For example, the control unit 120 may be configured by a set of one or more processors. As an example, the control unit 120 may be configured by a set of a communication control processor, an application processor (AP), an electronic control unit (ECU), a graphical processing unit, and a memory control processor. As another example, the memory unit 90 may be configured by a RAM, a DRAM, a ROM, a flash memory, a volatile memory, a non-volatile memory, and/or a combination thereof.

FIG. 4 shows an example of UE to which implementations of the present disclosure is applied.

Referring to FIG. 4 , a UE 100 may correspond to the first wireless device 100 of FIG. 2 and/or the wireless device 100 or 200 of FIG. 3 .

A UE 100 includes a processor 102, a memory 104, a transceiver 106, one or more antennas 108, a power management module 110, a battery 112, a display 110, a keypad 116, a subscriber identification module (SIM) card 118, a speaker 120, and a microphone 122.

The processor 102 may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The processor 102 may be configured to control one or more other components of the UE 100 to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. Layers of the radio interface protocol may be implemented in the processor 102. The processor 102 may include ASIC, other chipset, logic circuit and/or data processing device. The processor 102 may be an application processor. The processor 102 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), a modem (modulator and demodulator). An example of the processor 102 may be found in SNAPDRAGON™ series of processors made by Qualcomm®, EXYNOS™ series of processors made by Samsung®, A series of processors made by Apple®, HELIO™ series of processors made by MediaTek®, ATOM™ series of processors made by Intel® or a corresponding next generation processor.

The memory 104 is operatively coupled with the processor 102 and stores a variety of information to operate the processor 102. The memory 104 may include ROM, RAM, flash memory, memory card, storage medium and/or other storage device. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The modules can be stored in the memory 104 and executed by the processor 102. The memory 104 can be implemented within the processor 102 or external to the processor 102 in which case those can be communicatively coupled to the processor 102 via various means as is known in the art.

The transceiver 106 is operatively coupled with the processor 102, and transmits and/or receives a radio signal. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 may include baseband circuitry to process radio frequency signals. The transceiver 106 controls the one or more antennas 108 to transmit and/or receive a radio signal.

The power management module 110 manages power for the processor 102 and/or the transceiver 106. The battery 112 supplies power to the power management module 110.

The display 110 outputs results processed by the processor 102. The keypad 116 receives inputs to be used by the processor 102. The keypad 116 may be shown on the display 110.

The SIM card 118 is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). It is also possible to store contact information on many SIM cards.

The speaker 120 outputs sound-related results processed by the processor 102. The microphone 122 receives sound-related inputs to be used by the processor 102.

FIG. 5 shows an example of a system architecture for a communication system to which technical features of the present disclosure can be applied. An example of the communication system may comprise a 5G system and/or NR system.

Referring to FIG. 5 , the communication system may comprise various core network entities, such as an access and mobility management function (AMF), a session management function (SMF), a user plane function (UPF), a policy control function (PCF), an authentication server function (AUSF), a unified data management (UDM), an application function (AF), a network exposure function (NEF), a network function repository function (NRF), a network slice selection function (NSSF), a network slice specific authentication and authorization function (NSSAAF) and a service communication proxy (SCP).

The AMF may support a termination of non-access stratum (NAS) signalling, NAS ciphering & integrity protection, registration management, connection management, mobility management, access authentication and authorization, security context management. The AMF may be associated with N1, N2 and Namf. The N1 is a reference point between the UE and the AMF. The N2 is a reference point between the RAN and the AMF. The Namf is a service-based interface exhibited by the AMF.

The SMF may support a session management (session establishment, modification, release), UE internet protocol (IP) address allocation & management, dynamic host configuration protocol (DHCP) functions, termination of NAS signalling related to session management, DL data notification, traffic steering configuration for UPF for proper traffic routing. The SMF may be associated with N4 and Nsmf. The N4 is a reference point between the SMF and the UPF. The Nsmf is a service-based interface exhibited by the SMF.

The UPF may support packet routing & forwarding, packet inspection, quality of service (QoS) handling, acts as external protocol data unit (PDU) session point of interconnect to Data Network (DN), and may be an anchor point for intra- & inter-radio access technology (RAT) mobility. The UPF may be associated with N3, N4, N6 and N9. The N3 is a reference point between the RAN and the UPF. The N6 is a reference point between the UPF and the DN. The N9 is a reference point between two UPFs.

The PCF may support unified policy framework, providing policy rules to control plane (CP) functions, access subscription information for policy decisions in a unified data repository (UDR). The PCF may be associated with Npcf. The Npcf is a service-based interface exhibited by the PCF.

The AUSF may act as an authentication server. The AUSF may be associated with Nausf. The Nausf is a service-based interface exhibited by the AUSF.

The UDM may support generation of Authentication and Key Agreement (AKA) credentials, user identification handling, access authorization, subscription management. The UDM may be associated with Nudm. The Nudm is a service-based interface exhibited by the UDM.

The AF may support application influence on traffic routing, accessing NEF, interaction with policy framework for policy control. The AF may be associated with Ng. The Naf is a service-based interface exhibited by the AF.

The NEF may support exposure of capabilities and events, secure provision of information from external application to 3GPP network, translation of internal/external information. The NEF may be associated with Nnef. The Nnef is a service-based interface exhibited by the NEF.

The NRF may support service discovery function, maintains NF profile and available NF instances. The NRF may be associated with Nnrf. The Nnrf is a service-based interface exhibited by the NRF.

The NSSF may support selecting of the Network Slice instances to serve the UE, determining the allowed network slice selection assistance information (NSSAI), determining the AMF set to be used to serve the UE. The NSSF may be associated with Nnssf. The Nnssf is a service-based interface exhibited by the NSSF.

The NSSAAF may support Network Slice-Specific Authentication and Authorization with a AAA Server (AAA-S). If the AAA-S belongs to a third party, the NSSAAF may contact the AAA-S via an a AAA proxy (AAA-P). The NSSAAF may be associated with Nnssaaf. The Nnssaaf is a service-based interface exhibited by the NSSAAF.

The SCP may support indirect communication, delegated discovery, message forwarding and routing to destination network function (NF)/NF service, Message forwarding and routing to a next hop SCP, communication security (e.g. authorization of the NF Service Consumer to access the NF Service Producer API), load balancing, monitoring, overload control, optionally interact with UDR, to resolve the UDM Group ID/UDR Group ID/AUSF Group ID/PCF Group ID/charging function (CHF) Group ID/home subscriber server (HSS) Group ID based on UE identity (e.g., subscription permanent identifier (SUPI) or international mobility subscriber identity (IMPI)/IP multimedia public identity (IMPU)).

FIG. 6 shows an example of the overall architecture of an NG-RAN to which technical features of the present disclosure can be applied.

Referring to FIG. 6 , a gNB may include a gNB-central unit (CU) (hereinafter, gNB-CU may be simply referred to as CU) and at least one gNB-distributed unit (DU) (hereinafter, gNB-DU may be simply referred to as DU).

The gNB-CU is a logical node hosting RRC, SDAP and PDCP protocols of the gNB or an RRC and PDCP protocols of the en-gNB. The gNB-CU controls the operation of the at least one gNB-DU.

The gNB-DU is a logical node hosting RLC, MAC, and physical layers of the gNB or the en-gNB. The operation of the gNB-DU is partly controlled by the gNB-CU. One gNB-DU supports one or multiple cells. One cell is supported by only one gNB-DU.

The gNB-CU and gNB-DU are connected via an F1 interface. The gNB-CU terminates the F1 interface connected to the gNB-DU. The gNB-DU terminates the F1 interface connected to the gNB-CU. One gNB-DU is connected to only one gNB-CU. However, the gNB-DU may be connected to multiple gNB-CUs by appropriate implementation. The F1 interface is a logical interface. For NG-RAN, the NG and Xn-C interfaces for a gNB consisting of a gNB-CU and gNB-DUs, terminate in the gNB-CU. For E-UTRAN-NR dual connectivity (EN-DC), the S1-U and X2-C interfaces for a gNB consisting of a gNB-CU and gNB-DUs, terminate in the gNB-CU. The gNB-CU and connected gNB-DUs are only visible to other gNBs and the 5GC as a gNB.

Functions of the F1 interface includes F1 control (F1-C) functions as follows.

(1) F1 Interface Management Function

The error indication function is used by the gNB-DU or gNB-CU to indicate to the gNB-CU or gNB-DU that an error has occurred.

The reset function is used to initialize the peer entity after node setup and after a failure event occurred. This procedure can be used by both the gNB-DU and the gNB-CU.

The F1 setup function allows to exchange application level data needed for the gNB-DU and gNB-CU to interoperate correctly on the F1 interface. The F1 setup is initiated by the gNB-DU.

The gNB-CU configuration update and gNB-DU configuration update functions allow to update application level configuration data needed between gNB-CU and gNB-DU to interoperate correctly over the F1 interface, and may activate or deactivate cells.

The F1 setup and gNB-DU configuration update functions allow to inform the single network slice selection assistance information (S-NSSAI) supported by the gNB-DU.

The F1 resource coordination function is used to transfer information about frequency resource sharing between gNB-CU and gNB-DU.

(2) System Information Management Function

Scheduling of system broadcast information is carried out in the gNB-DU. The gNB-DU is responsible for transmitting the system information according to the scheduling parameters available.

The gNB-DU is responsible for the encoding of NR master information block (MIB). In case broadcast of system information block type-1 (SIB1) and other SI messages is needed, the gNB-DU is responsible for the encoding of SIB1 and the gNB-CU is responsible for the encoding of other SI messages.

(3) F1 UE context management function

The F1 UE context management function supports the establishment and modification of the necessary overall UE context.

The establishment of the F1 UE context is initiated by the gNB-CU and accepted or rejected by the gNB-DU based on admission control criteria (e.g., resource not available).

The modification of the F1 UE context can be initiated by either gNB-CU or gNB-DU. The receiving node can accept or reject the modification. The F1 UE context management function also supports the release of the context previously established in the gNB-DU. The release of the context is triggered by the gNB-CU either directly or following a request received from the gNB-DU. The gNB-CU request the gNB-DU to release the UE Context when the UE enters RRC_IDLE or RRC_INACTIVE.

This function can be also used to manage DRBs and SRBs, i.e., establishing, modifying and releasing DRB and SRB resources. The establishment and modification of DRB resources are triggered by the gNB-CU and accepted/rejected by the gNB-DU based on resource reservation information and QoS information to be provided to the gNB-DU. For each DRB to be setup or modified, the S-NSSAI may be provided by gNB-CU to the gNB-DU in the UE context setup procedure and the UE context modification procedure.

The mapping between QoS flows and radio bearers is performed by gNB-CU and the granularity of bearer related management over F1 is radio bearer level. For NG-RAN, the gNB-CU provides an aggregated DRB QoS profile and QoS flow profile to the gNB-DU, and the gNB-DU either accepts the request or rejects it with appropriate cause value. To support packet duplication for intra-gNB-DU carrier aggregation (CA), one data radio bearer should be configured with two GPRS tunneling protocol (GTP)-U tunnels between gNB-CU and a gNB-DU.

With this function, gNB-CU requests the gNB-DU to setup or change of the special cell (SpCell) for the UE, and the gNB-DU either accepts or rejects the request with appropriate cause value.

With this function, the gNB-CU requests the setup of the secondary cell(s) (SCell(s)) at the gNB-DU side, and the gNB-DU accepts all, some or none of the SCell(s) and replies to the gNB-CU. The gNB-CU requests the removal of the SCell(s) for the UE.

(4) RRC Message Transfer Function

This function allows to transfer RRC messages between gNB-CU and gNB-DU. RRC messages are transferred over F1-C. The gNB-CU is responsible for the encoding of the dedicated RRC message with assistance information provided by gNB-DU.

(5) Paging Function

The gNB-DU is responsible for transmitting the paging information according to the scheduling parameters provided.

The gNB-CU provides paging information to enable the gNB-DU to calculate the exact paging occasion (PO) and paging frame (PF). The gNB-CU determines the paging assignment (PA). The gNB-DU consolidates all the paging records for a particular PO, PF and PA, and encodes the final RRC message and broadcasts the paging message on the respective PO, PF in the PA.

(6) Warning Messages Information Transfer Function

This function allows to cooperate with the warning message transmission procedures over NG interface. The gNB-CU is responsible for encoding the warning related SI message and sending it together with other warning related information for the gNB-DU to broadcast over the radio interface.

FIG. 7 shows an example of a dual connectivity (DC) architecture to which technical features of the present disclosure can be applied.

Referring to FIG. 7 , MN 711, SN 721, and a UE 730 communicating with both the MN 711 and the SN 721 are illustrated. As illustrated in FIG. 7 , DC refers to a scheme in which a UE (e.g., UE 730) utilizes radio resources provided by at least two RAN nodes comprising a MN (e.g., MN 711) and one or more SNs (e.g., SN 721). In other words, DC refers to a scheme in which a UE is connected to both the MN and the one or more SNs, and communicates with both the MN and the one or more SNs. Since the MN and the SN may be in different sites, a backhaul between the MN and the SN may be construed as non-ideal backhaul (e.g., relatively large delay between nodes).

MN (e.g., MN 711) refers to a main RAN node providing services to a UE in DC situation. SN (e.g., SN 721) refers to an additional RAN node providing services to the UE with the MN in the DC situation. If one RAN node provides services to a UE, the RAN node may be a MN. SN can exist if MN exists.

For example, the MN may be associated with macro cell whose coverage is relatively larger than that of a small cell. However, the MN does not have to be associated with macro cell—that is, the MN may be associated with a small cell. Throughout the disclosure, a RAN node that is associated with a macro cell may be referred to as ‘macro cell node’. MN may comprise macro cell node.

For example, the SN may be associated with small cell (e.g., micro cell, pico cell, femto cell) whose coverage is relatively smaller than that of a macro cell. However, the SN does not have to be associated with small cell—that is, the SN may be associated with a macro cell. Throughout the disclosure, a RAN node that is associated with a small cell may be referred to as ‘small cell node’. SN may comprise small cell node.

The MN may be associated with a master cell group (MCG). MCG may refer to a group of serving cells associated with the MN, and may comprise a primary cell (PCell) and optionally one or more secondary cells (SCells). User plane data and/or control plane data may be transported from a core network to the MN through a MCG bearer. MCG bearer refers to a bearer whose radio protocols are located in the MN to use MN resources. As shown in FIG. 7 , the radio protocols of the MCG bearer may comprise PDCP, RLC, MAC and/or PHY.

The SN may be associated with a secondary cell group (SCG). SCG may refer to a group of serving cells associated with the SN, and may comprise a primary secondary cell (PSCell) and optionally one or more SCells. User plane data may be transported from a core network to the SN through a SCG bearer. SCG bearer refers to a bearer whose radio protocols are located in the SN to use SN resources. As shown in FIG. 7 , the radio protocols of the SCG bearer may comprise PDCP, RLC, MAC and PHY.

User plane data and/or control plane data may be transported from a core network to the MN and split up/duplicated in the MN, and at least part of the split/duplicated data may be forwarded to the SN through a split bearer. Split bearer refers to a bearer whose radio protocols are located in both the MN and the SN to use both MN resources and SN resources. As shown in FIG. 7 , the radio protocols of the split bearer located in the MN may comprise PDCP, RLC, MAC and PHY. The radio protocols of the split bearer located in the SN may comprise RLC, MAC and PHY.

According to various embodiments, PDCP anchor/PDCP anchor point/PDCP anchor node refers to a RAN node comprising a PDCP entity which splits up and/or duplicates data and forwards at least part of the split/duplicated data over X2/Xn interface to another RAN node. In the example of FIG. 7 , PDCP anchor node may be MN.

According to various embodiments, the MN for the UE may be changed. This may be referred to as handover, or a MN handover.

According to various embodiments, a SN may newly start providing radio resources to the UE, establishing a connection with the UE, and/or communicating with the UE (i.e., SN for the UE may be newly added). This may be referred to as a SN addition.

According to various embodiments, a SN for the UE may be changed while the MN for the UE is maintained. This may be referred to as a SN change.

According to various embodiments, DC may comprise E-UTRAN NR-DC (EN-DC), and/or multi-radio access technology (RAT)-DC (MR-DC). EN-DC refers to a DC situation in which a UE utilizes radio resources provided by E-UTRAN node and NR RAN node. MR-DC refers to a DC situation in which a UE utilizes radio resources provided by RAN nodes with different RATs.

Hereinafter, signalling radio bearer (SRB) is described.

Signalling radio bearer may be defined as a radio bearer (RB) that is used only for a transmission of RRC and/or NAS messages. More specifically, the following SRBs may be defined:

-   -   SRB0 may be used for RRC messages using the CCCH logical         channel;     -   SRB1 may be used for for RRC messages (which may include a         piggybacked NAS message) as well as for NAS messages prior to         the establishment of SRB2, all using DCCH logical channel;     -   SRB2 may be used for NAS messages and for RRC messages which         include logged measurement information, all using DCCH logical         channel. SRB2 has a lower priority than SRB1 and may be         configured by the network after AS security activation; and     -   SRB3 may be used for specific RRC messages when UE is in DC         (e.g., (NG)EN-DC and/or NR-DC), all using DCCH logical channel.

In downlink, piggybacking of NAS messages may be used only for one dependant (i.e. with joint success/failure) procedure: bearer establishment/modification/release. In uplink, piggybacking of NAS message may be used only for transferring the initial NAS message during connection setup and connection resume.

The NAS messages transferred via SRB2 may also be contained in RRC messages, which however do not include any RRC protocol control information.

Once AS security is activated, all RRC messages on SRB1, SRB2 and SRB3, including those containing NAS messages, may be integrity protected and ciphered by PDCP. NAS may independently apply integrity protection and ciphering to the NAS messages.

Split SRB may be supported for all the MR-DC options in both SRB1 and SRB2 (split SRB may not be supported for SRB0 and SRB3).

For operation with shared spectrum channel access, SRB0, SRB1 and SRB3 may be assigned with the highest priority Channel Access Priority Class (CAPC), (i.e. CAPC=1) while CAPC for SRB2 is configurable.

FIG. 8 shows an example of possible RRC states in a wireless communication system to which technical features of the present disclosure can be applied.

Referring to FIG. 8 , there may be 3 possible RRC states in a wireless communication system (i.e., RRC_IDLE, RRC_CONNECTED and/or RRC_IDLE).

In RRC_IDLE (or, idle mode/state), RRC context for communication between a UE and a network may not be established in RAN, and the UE may not belong to a specific cell. Also, in RRC_IDLE, there is no core network connection for the UE. Since the device remains in sleep mode in most of the time to reduce battery consumption, data transfer between the UE and the network may not occur. UEs in RRC_IDLE may periodically wake-up to receive paging messages from the network. Mobility may be handled by the UE through cell reselection. Since uplink synchronization is not maintained, the UE may not perform uplink transmission other than transmissions for random access (e.g., random access preamble transmission) to move to RRC_CONNECTED.

In RRC_CONNECTED (or, connected state/mode), RRC context for communication between a UE and a network may be established in RAN. Also, in RRC_CONNECTED, core network connection is established for the UE. Since the UE belongs to a specific cell, cell-radio network temporary identifier (C-RNTI) for signallings between the UE and the network may be configured for the UE. Data transfer between the UE and the network may occur. Mobility may be handled by the network—that is, the UE may provide measurement report to the network, and the network may transmit mobility commands to the UE to perform a mobility. Uplink time alignment may need to be established based on a random access and maintained for data transmission.

In RRC_INACTIVE (or, inactive state/mode), RRC context for communication between a UE and a network may be kept in RAN. Data transfer between the UE and the network may not occur. Since core network connection may also be kept for the UE, the UE may fast transit to a connected state for data transfer. In the transition, core network signalling may not be needed. The RRC context may be already established in the network and idle-to-active transitions can be handled in the RAN. The UE may be allowed to sleep in a similar way as in RRC_IDLE, and mobility may be handled through cell reselection without involvement of the network. The RRC_INCATIVE may be construed as a mix of the idle state and the connected state.

As illustrated in FIG. 8 , the UE may transit to RRC_CONNECTED from RRC_IDLE by performing initial attach procedure or RRC connection establishment procedure. The UE may transit to RRC_IDLE from RRC_CONNECTED when detach, RRC connection release and/or connection failure (e.g., radio link failure (RLF)) has occurred. The UE may transit to RRC_INACTIVE from RRC_INACTIVE when RRC connection is suspended, and transit to RRC_CONNECTED from RRC_INACTIVE when RRC connection is resume. The UE may transit to RRC_IDLE from RRC_INACTIVE when connection failure such as RLF has occurred.

Hereinafter, activity notification is described.

For EN-DC, the activity notification function may be used to report user plane activity within SN resources. The activity notification function may be used to either report inactivity or resumption of activity after inactivity was reported. In EN-DC, the activity reporting may be provided from the SN only. The MN may take further actions.

Support of activity notification in EN-DC may be used to keep the MN informed about user traffic activity in resources owned by the SN. The MN may take appropriate action upon receiving such notification.

For example, the SN may transmit an activity notification message informing a user data inactivity of resources owned by the SN to the MN. After/upon receiving the activity notification message, the MN may decide to keep SN resources. After a while, the SN may transmit an activity notification message informing a resumption of user plane activity.

For MR-DC with 5GC, the activity notification function may be used to report user plane activity within SN resources or to report a RAN paging failure event to the SN. The activity notification function may be used to either report inactivity or resumption of activity after inactivity was reported. In MR-DC with 5GC, the activity reporting may be provided from the SN only. The MN may take further actions. RAN paging failure reporting may be provided from the MN only.

For example, the SN may transmit the activity notification message informing a user data inactivity. After/upon receiving the activity notification message, the MN may decide further actions that impact SN resources (e.g., send UE to RRC_INACTIVE, bearer reconfiguration). For example, MN may take no action. After a while, the SN may transmit an activity notification message informing a resumption of user plane activity to the MN, notifying the MN that the (UE or PDU Session or QoS flow) is no longer inactive.

According to various embodiments of the present disclosure, the activity notification message (or, activity notification) may be transmitted from the SN to the MN. The activity notification message may indicate an activity status for SN resources (i.e., resources owned by the SN) and/or SN terminated bearers.

The activity status may comprise:

-   -   user plane/data/traffic inactivity (i.e., inactivity status         information); or     -   a resumption/reactivation of user plane/data/traffic activity         (i.e., activity status information).

FIGS. 9A and 9B show a first example of MR-DC with 5GC with RRC_INACTIVE to which technical features of the present disclosure can be applied.

The activity notification function may be used to enable MR-DC with 5GC with RRC_INACTIVE operation. The MN node may decide, after inactivity is reported from the SN and also MN resources show no activity, to send the UE to RRC_INACTIVE. Resumption to RRC_CONNECTED may take place after activity is reported from the SN for SN terminated bearers.

FIGS. 9A and 9B shows how activity notification function interacts with NG-RAN functions for RRC_INACTIVE and SN modification procedures in order to keep the higher layer MR-DC NG-RAN resources established for UEs in RRC_INACTIVE, including NG and Xn interface C-plane, U-plane and bearer contexts established while lower layer MCG and SCG resources are released. NG-RAN may memorise the cell group configuration for MCG in order to apply delta signalling at resume. After the UE has transited successfully back to RRC_CONNECTED, lower layer SCG resources may be established afterwards by means of RRC connection reconfiguration.

Referring to FIG. 9A, in step S901, the SN may transmit an activity notification message indicating a user data inactivity for SN terminated bearers to the MN.

In step S903, the MN may decide to send the UE to RRC_INACTIVE.

In step S905, the MN may transmit an SN modification request message indicating to release lower layers to the SN. The MN may trigger the MN initiated SN Modification procedure, requesting the SN to release lower layers.

In step S907, the SN may transmit a SN modification request acknowledge (ACK) message, as a response for the SN modification request message.

In step S909, the UE may be sent to RRC_INACTIVE.

In step S911, a period of inactivity may proceed.

In step S913, after the period of inactivity, the SN may transmit an activity notification a resumption/reactivation of user data activity to the MN.

In step S915, the UE may return to RRC_CONNECTED.

In an example, the MN may decide whether to reactivate the SN terminated bearers. If (e.g. due to UE mobility), MN decides not to reactivate the SN terminated bearers, the MN may initiate the MN initiated SN release procedure and the procedure may end.

Steps in FIG. 9A may continue to those in FIG. 9B.

Referring to FIG. 9B, in step S917, the MN may trigger the MN initiated SN modification procedure to re-establish lower layers via SN modification request message.

In step S919, the SN may transmit an SN modification request ACK message carrying SN RRC reconfiguration message to the MN. The SN may provide configuration data within the SN RRC configuration/reconfiguration message.

In step S921 to step S927, the RRC connection reconfiguration procedure commences.

In step S921, the MN may transmit RRC reconfiguration message to the UE.

In step S923, the UE may transmit RRC reconfiguration complete message carrying SN RRC reconfiguration complete to the MN.

In step S925, the MN may transmit the SN reconfiguration complete message carrying SN RRC reconfiguration complete to the SN.

In step S927, the UE may perform a random access procedure towards the SN.

FIGS. 10A and 10B show a second example of MR-DC with 5GC with RRC_INACTIVE to which technical features of the present disclosure can be applied.

The activity notification function may be used to enable MR-DC with 5GC with RRC_INACTIVE operation. The MN node may decide, after inactivity is reported from the SN and also MN resources show no activity, to send the UE to RRC_INACTIVE, while keeping the SCG configuration. Resumption to RRC_CONNECTED may take place after activity is reported from the SN for SN terminated bearers.

FIGS. 10A and 10B show how activity notification function interacts with NG-RAN functions for RRC_INACTIVE and SN modification procedures in order to keep the full MR-DC NG-RAN resources established for UEs in RRC_INACTIVE. When the UE transits successfully back to RRC_CONNECTED, lower layer MCG and SCG configurations may be restored or reconfigured by means of RRC (Connection) resume.

Referring to FIG. 10A, in step S1001, the SN may transmit an activity notification message indicating a user data inactivity for SN terminated bearers to the MN.

In step S1003, the MN may decide to send the UE to RRC_INACTIVE.

In step S1005, the MN may transmit SN modification request message indicating to suspend lower layers to the SN. The MN may trigger the MN initiated SN Modification procedure, requesting the SN to suspend lower layers.

In step S1007, the SN may transmit SN modification request ACK message, as a response for the SN modification request message.

In step S1009, the UE may be sent to RRC_INACTIVE.

In step S1011, a period of inactivity may proceed.

In step S1013, the SN may transmit activity notification indicating a resumption/reactivation of user data activity to the MN.

In step S1015, after a period of inactivity, upon receiving the activity notification from the SN, the MN may decide to return the UE to RRC_CONNECTED.

In an embodiment, the MN may decide whether to reactivate the SN terminated bearers. If (e.g. due to UE mobility), the MN decides not to reactivate the SN terminated bearers, the MN may initiate the MN initiated SN release procedure, rather than the MN initiated SN modification procedure in step S1017 and S1019.

Steps in FIG. 10A may continue to those in FIG. 10B.

Referring to FIG. 10B, in step S1017, the MN may transmit SN modification request message indicating to resume lower layers to the SN. The MN may trigger the MN initiated SN Modification procedure to resume the SCG lower layers.

In step S1019, the SN may transmit a SN modification request ACK message carrying SN RRC reconfiguration message. If the SCG configuration needs to be updated, the SN may provide the configuration data within an SN RRC configuration message.

In step S1021 and S1023, the RRC (Connection) resume procedure may commence, where the UE is instructed to resume both the MCG and the SCG. If the SCG configuration is to be updated, the new configuration may be provided in the RRC(Connection)Resume message.

In step S1025, the MN may inform the SN that the UE has completed the reconfiguration procedure successfully, via the SN Reconfiguration Complete message, including the SN RRC response message, if received from the UE.

In step S1027, if instructed, the UE may perform synchronisation towards the PSCell of the SN.

Meanwhile, in DC, UE's power consumption may need to be reduced. A DC UE (e.g., UE such as UE 730) may be easy to be heated for reserving communication services. The SCG deactivation may be a good way to save power for a UE in case of no data packets coming from the SN. On the other hand, if data packets comes again, the SN should be connected quickly to receive the service quickly. UE behaviors and network behaviors should be defined for realizing the SCG activation/deactivation. Various embodiments of the present disclosure may facilitate the efficient activation/deactivation of the SCG for a UE, including PSCell.

The following drawings are created to explain specific embodiments of the present disclosure. The names of the specific devices or the names of the specific signals/messages/fields shown in the drawings are provided by way of example, and thus the technical features of the present disclosure are not limited to the specific names used in the following drawings.

FIG. 11 shows an example of a method for SCG deactivation according to an embodiment of the present disclosure. Steps illustrated in FIG. 11 may be performed by a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC).

Referring to FIG. 11 , in step S1101, the CU may transmit, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN. The one or more cells may comprise a primary secondary cell (PSCell).

In step S1103, the CU may receive, from the DU, a second message comprising information informing a successful deactivation of the one or more cells.

In step S1105, the CU may determine a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device. The list of cells may comprise the PSCell.

In step S1107, the CU may transmit, to the DU, a third message comprising information informing the list of cells to be activated in the SCG.

In step S1109, the CU may receive, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to various embodiments, the first message may further comprise at least one of: a discontinuous reception (DRX) configuration comprising information to increase an off duration of a DRX cycle for the one or more cells; or an instruction to store a configuration of the one or more cells

According to various embodiments, the first message may further comprise information informing the one or more cells to be deactivated.

According to various embodiments, the first message may further comprise an instruction to store a configuration of the wireless device for the one or more cells.

According to various embodiments, the third message may further comprise an instruction to activate the list of cells.

According to various embodiments, the first message may be a user equipment (UE) context modification request message. The second message may be a UE context modification response message.

According to various embodiments, the third message may be a user equipment (UE) context modification request message. The fourth message may be a UE context modification response message.

According to various embodiments, the CU may transmit, to the MN, an activity notification message comprising the amount of packets received by the CU. The CU may receive, from the MN, at least one of information informing the list of cells to be activated, or an instruction to activate the list of cells.

According to various embodiments, at least one of the information informing the list of cells to be activated, or the instruction to activate the list of cells may be received via a SN modification request message.

FIG. 12 shows an example of a method for performing a communication in a SCG deactivation state according to an embodiment of the present disclosure. Steps illustrated in FIG. 12 may be performed by a wireless device (and/or a UE) served by a master node (MN) and a secondary node (SN) in a dual connectivity (DC).

Referring to FIG. 12 , in step S1201, the wireless device may enter a secondary cell group (SCG) deactivation state for an SCG related to the SN.

In step S1203, in the SCG deactivation state, the wireless device may communicate with the MN while skipping a physical downlink control channel (PDCCH) monitoring for one or more cells in the SCG that are deactivated. The one or more cells may comprise a primary secondary cell (PSCell)

In step S1205, the wireless device may switch from the SCG deactivation state to an SCG activation state for the SCG.

In step S1207, in the SCG activation state, the wireless device may communicate with the MN and the SN while performing a PDCCH monitoring for a list of cells in the SCG that is activated. The list of cells may comprise the PSCell. The list of cells is determined based on at least one of: an amount of packets to be transmitted to the wireless device or by the wireless device; or a measurement report transmitted by the wireless device.

FIG. 13 shows an example of a procedure for SCG activation/deactivation for a dual connected UE according to an embodiment of the present disclosure.

Referring to FIG. 13 , in step S1301, a CU of SN may send a UE CONTEXT MODIFICATION REQUEST message to a DU of the SN to deactivate an SCG of the UE. After step S1301, the UE may be in RRC_CONNECTED state or RRC_INACTIVE state. The UE CONTEXT MODIFICATION REQUEST message may comprise at least one of:

-   -   Indication/instruction for SCG deactivation, dormant SCG         (PScell);     -   Configuration of long DRX for PScell, Scells in dormant; or     -   Instruction to store a configuration of PScell, and/or dormant         Scells.

In step S1303, the DU of the SN perform behaviours based on the information received in step S1301 (e.g., indication/instruction for SCG deactivation, dormant SCG (PScell), configuration of long DRX for PScell, Scells in dormant, and/or instruction to store a configuration of PScell, and/or dormant Scells). Then, the DU of the SN may send a UE CONTEXT MODIFICATION RESPONSE to the CU of the SN, including a successful indication based on the specific information received in step S1301. For example, the UE CONTEXT MODIFICATION RESPONSE may comprise information informing a successful deactivation of the SCG, and/or information informing that the SCG is successfully deactivated based on the specific information received in step S1301.

In step S1305, after some time, if packets comes to the CU of the SN, the SCG should be activated. Then, the CU of the SN may send an activation notification to MN. The activity notification may comprise an amount of the packets. The MN may decide the SCG PScell and/or Scells to be activated based on measurements (e.g., measurement report) the MN received and also the packets that the MN received if the MN has.

In step S1307, the MN may send an SN Modification Request message to the CU of the SN. The SN Modification Request message may comprise an indication/instruction of SCG activation and/or a list of all or part of cells to be activated, including the SCG PScell and/or Scells.

Step S1305 and S1307 may be optional (i.e., may be omitted), if SRB3 is configured and the CU of the SN can receive the measurement report from the UE by itself. The CU of the SN can decide a list of cells to be activated itself including the SCG PScell and/or Scells based on the measurement report and also amount of packets coming from a core network (CN).

In step S1309, the CU of the SN may send the UE CONTEXT MODIFICATION REQUEST message to the DU of the SN. The UE CONTEXT MODIFICATION REQUEST message may comprise the list of cells to be activated including the SCG PScell and/or Scells.

In step S1311, the DU of the SN may find the UE context based on the UE F1AP ID and activate the list of cells including the SCG PScell and/or Scells.

In step S1313, the DU of the SN may send the UE CONTEXT MODIFICATION RESPONSE message to the CU of SN, and use the previously stored configuration for the UE in the list of cells including the SCG PSCell and/or SCells. For example, the UE CONTEXT MODIFICATION RESPONSE message may comprise information informing a successful activation of the list of cells, and/or information informing that the list of cells is successfully activated.

In step S1315, if the SCG configuration needs to be updated, the SN may provide the configuration data within an SN RRC (re)configuration message.

In step S1317, the MN may transmit an RRC resume message and/or an RRC reconfiguration message to the UE, for instructing the UE to activate the SCG. If the SCG configuration is to be updated, the new configuration may be provided in the RRC message (e.g., RRC resume message and/or RRC reconfiguration message).

In step S1319, The UE may transmit an RRC resume complete message comprising an SN RRC reconfiguration complete message.

In step S1321, the MN may inform the SN that the UE has completed the reconfiguration procedure successfully, via the SN Reconfiguration Complete message, including the SN RRC response message, if received from the UE.

Steps S1315 to S1321 may be optional (i.e., may be omitted), if SRB3 is configured and the CU of the SN can configure the RRC information by itself

Hereinafter, an apparatus for a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system, according to some embodiments of the present disclosure, will be described.

For example, the CU may include at least one processor, a transceiver, and a memory.

For example, the at least one processor may be configured to be coupled operably with the memory and the transceiver.

The at least one processor may be configured to control the transceiver to transmit, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN. The one or more cells may comprise a primary secondary cell (PSCell). The at least one processor may be configured to control the transceiver to receive, from the DU, a second message comprising information informing a successful deactivation of the one or more cells. The at least one processor may be configured to determine a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device. The list of cells may comprise the PSCell. The at least one processor may be configured to control the transceiver to transmit, to the DU, a third message comprising information informing the list of cells to be activated in the SCG. The at least one processor may be configured to control the transceiver to receive, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

According to various embodiments, the first message may further comprise at least one of: a discontinuous reception (DRX) configuration comprising information to increase an off duration of a DRX cycle for the one or more cells; or an instruction to store a configuration of the one or more cells

According to various embodiments, the first message may further comprise information informing the one or more cells to be deactivated.

According to various embodiments, the first message may further comprise an instruction to store a configuration of the wireless device for the one or more cells.

According to various embodiments, the third message may further comprise an instruction to activate the list of cells.

According to various embodiments, the first message may be a user equipment (UE) context modification request message. The second message may be a UE context modification response message.

According to various embodiments, the third message may be a user equipment (UE) context modification request message. The fourth message may be a UE context modification response message.

According to various embodiments, the at least one processor may be configured to control the transceiver to transmit, to the MN, an activity notification message comprising the amount of packets received by the CU. The at least one processor may be configured to control the transceiver to receive, from the MN, at least one of information informing the list of cells to be activated, or an instruction to activate the list of cells.

According to various embodiments, at least one of the information informing the list of cells to be activated, or the instruction to activate the list of cells may be received via a SN modification request message.

Hereinafter, an apparatus for a wireless device (and/or UE) served by a master node (MN) and a secondary node (SN) in a dual connectivity (DC) in a wireless communication system, according to some embodiments of the present disclosure, will be described.

For example, the wireless device may include at least one processor, a transceiver, and a memory.

For example, the at least one processor may be configured to be coupled operably with the memory and the transceiver.

The at least one processor may be configured to enter a secondary cell group (SCG) deactivation state for an SCG related to the SN. The at least one processor may be configured to control the transceiver to communicate with the MN while skipping a physical downlink control channel (PDCCH) monitoring for one or more cells in the SCG that are deactivated. The one or more cells may comprise a primary secondary cell (PSCell). The at least one processor may be configured to switch from the SCG deactivation state to an SCG activation state for the SCG. The at least one processor may be configured to control the transceiver to communicate with the MN and the SN while performing a PDCCH monitoring for a list of cells in the SCG that is activated. The list of cells may comprise the PSCell. The list of cells is determined based on at least one of: an amount of packets to be transmitted to the wireless device or by the wireless device; or a measurement report transmitted by the wireless device.

Hereinafter, a processor for a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system, according to some embodiments of the present disclosure, will be described.

A memory of the CU may store software code which implements instructions that, when executed by the processor, perform operations comprising: transmitting, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receiving, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determining a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmitting, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receiving, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

Hereinafter, a non-transitory computer-readable medium has stored thereon a plurality of instructions for a central unit (CU) of a secondary node (SN) serving a wireless device with a master node (MN) in a dual connectivity (DC) in a wireless communication system, according to some embodiments of the present disclosure, will be described.

According to some embodiment of the present disclosure, the technical features of the present disclosure could be embodied directly in hardware, in a software executed by a processor, or in a combination of the two. For example, a method performed by a wireless device in a wireless communication may be implemented in hardware, software, firmware, or any combination thereof. For example, a software may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other storage medium.

Some example of storage medium is coupled to the processor such that the processor can read information from the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. For other example, the processor and the storage medium may reside as discrete components.

The computer-readable medium may include a tangible and non-transitory computer-readable storage medium.

For example, non-transitory computer-readable media may include random access memory (RAM) such as synchronous dynamic random access memory (SDRAM), read-only memory (ROM), non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), FLASH memory, magnetic or optical data storage media, or any other medium that can be used to store instructions or data structures. Non-transitory computer-readable media may also include combinations of the above.

In addition, the method described herein may be realized at least in part by a computer-readable communication medium that carries or communicates code in the form of instructions or data structures and that can be accessed, read, and/or executed by a computer.

According to some embodiment of the present disclosure, a non-transitory computer-readable medium has stored thereon a plurality of instructions. The stored a plurality of instructions may be executed by a processor of the CU.

The stored a plurality of instructions may cause the CU to: transmit, to a distributed unit (DU) of the SN, a first message comprising an instruction to deactivate one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells comprise a primary secondary cell (PSCell); receive, from the DU, a second message comprising information informing a successful deactivation of the one or more cells; determine a list of cells to be activated in the SCG based on at least one of an amount of packets received by the CU or a measurement report received from the wireless device, wherein the list of cells comprises the PSCell; transmit, to the DU, a third message comprising information informing the list of cells to be activated in the SCG; and receive, from the DU, a fourth message comprising information informing a successful activation of the list of cells.

All the messages in the present disclosure are examples by using the existing procedures, but they are not limited. That is, new messages can be defined to realize the same goal.

The present disclosure may have various advantageous effects.

For example, UE's service experience can be enhanced in DC since UE's power consumption can be reduced if there are no data packets to be transmitted during a deactivation state and when packets arrive again, UE and network can go to connected mode quickly to receive the services.

Advantageous effects which can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand and/or derive from the present disclosure. Accordingly, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that may be understood or derived from the technical features of the present disclosure.

Claims in the present disclosure can be combined in a various way. For instance, technical features in method claims of the present disclosure can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims can be combined to be implemented or performed in a method. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in an apparatus. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in a method. Other implementations are within the scope of the following claims. 

1. A method performed by a central unit (CU) of a secondary node (SN) serving a user equipment (UE) with a master node (MN) in a dual connectivity (DC) in a wireless communication system, the method comprising: transmitting, to a distributed unit (DU) of the SN, a user equipment (UE) context modification request message comprising information for requesting a status change of one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells in the SCG includes a primary secondary cell (PSCell); receiving, from the DU, a UE context modification response message comprising information for a status of the one or more cells in the SCG; and transferring, to the MN, a radio resource control (RRC) reconfiguration message related to the status of the one or more cells in the SCG, wherein the status comprises at least one of activation or deactivation, and wherein the status change comprises at least one of a change from activation to deactivation or a change from deactivation to activation.
 2. The method of claim 1, further comprising transmitting a message comprising at least one of: a discontinuous reception (DRX) configuration comprising information to increase an off duration of a DRX cycle for the one or more cells; or an instruction to store a configuration of the one or more cells.
 3. The method of claim 2, wherein the message further comprises information informing the one or more cells to be deactivated.
 4. The method of claim 2, wherein the message further comprises an instruction to store a configuration of the UE for the one or more cells.
 5. The method of claim 1, wherein the UE context modification request message further comprises a list of cells for the status change in the SCG. 6-7. (canceled)
 8. The method of claim 1, further comprising: transmitting, to the MN, an activity notification message comprising an amount of packets received by the CU; and receiving, from the MN, at least one of information informing a list of cells for the status change in the SCG, or an instruction for the status change.
 9. The method of claim 1, further comprising receiving, from the MN, a SN modification request message comprising information for requesting the status change.
 10. The method of claim 1, wherein the UE is in communication with at least one of a network, or autonomous vehicles other than the UE.
 11. A central unit (CU) of a secondary node (SN) serving a user equipment (UE) with a master node (MN) in a dual connectivity (DC) in a wireless communication system, the CU comprising: at least one transceiver; at least one processor; and at least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising: transmitting, to a distributed unit (DU) of the SN, a user equipment (UE) context modification request message comprising information for requesting a status change of one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells in the SCG includes a primary secondary cell (PSCell); receiving, from the DU, a UE context modification response message comprising information for a status of the one or more cells in the SCG; and transferring, to the MN, a radio resource control (RRC) reconfiguration message related to the status of the one or more cells in the SCG, wherein the status comprises at least one of activation or deactivation, and wherein the status change comprises at least one of a change from activation to deactivation or a change from deactivation to activation.
 12. The CU of claim 11, wherein the operations further comprise transmitting a message comprising at least one of: a discontinuous reception (DRX) configuration comprising information to increase an off duration of a DRX cycle for the one or more cells; or an instruction to store a configuration of the one or more cells.
 13. The CU of claim 12, wherein the message further comprises information informing the one or more cells to be deactivated.
 14. The CU of claim 12, wherein the message further comprises an instruction to store a configuration of the UE for the one or more cells. 15-17. (canceled)
 18. A user equipment (UE) served by a master node (MN) and a secondary node (SN) in a dual connectivity (DC) in a wireless communication system, the UE comprising: at least one transceiver; at least one processor; and at least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising: receiving, from the MN, a radio resource control (RRC) reconfiguration message related to a status of one or more cells in a secondary cell group (SCG) related to the SN, wherein the one or more cells in the SCG includes a primary secondary cell (PSCell); entering the status based on the RRC reconfiguration message; and transmitting, to the MN, an RRC reconfiguration complete message as a response for the RRC reconfiguration message, wherein, before receiving the RRC reconfiguration message: a UE context modification request message comprising information for requesting a status change of the one or more cells in the SCG is transmitted from a central unit (CU) of the SN to a distributed unit (DU) of the SN, a UE context modification response message comprising information for the status of the one or more cells in the SCG is transmitted from the DU to the CU; and the RRC reconfiguration message related to the status of the one or more cells in the SCG is transferred from the CU to the MN, wherein the status comprises at least one of activation or deactivation, and wherein the status change comprises at least one of a change from activation to deactivation or a change from deactivation to activation.
 19. The method of claim 1, wherein the RRC reconfiguration message is transferred from the CU to the MN via a SN modification request acknowledgement message.
 20. The CU of claim 11, wherein the operations further comprise receiving, from the MN, a SN modification request message comprising information for requesting the status change.
 21. The CU of claim 11, wherein the RRC reconfiguration message is transferred from the CU to the MN via a SN modification request acknowledgement message.
 22. The UE of claim 18, wherein, before receiving the RRC reconfiguration message, a SN modification request message comprising information for requesting the status change is transmitted from the MN to the CU.
 23. The UE of claim 18, wherein the RRC reconfiguration message is transferred from the CU to the MN via a SN modification request acknowledgement message. 